On Tue, 19 Jan 2016, Richard Biener wrote:
>
> The following should fix PR69352 where hash collisions make
> equal_mem_array_ref_p get refs it wasn't supposed to compare
> and will not compare correctly (those with variable indices).
>
> Profiledbootstrap and testing running on x86_64-unknown-linux-gnu.
The following is an updated patch based on comments - handles
size == -1 properly as well as the reverse storage order flag.
Richard.
2016-01-19 Richard Biener <rguent...@suse.de>
PR tree-optimization/69352
* tree-ssa-scopedtables.c (equal_mem_array_ref_p): Constrain
max size properly.
* gcc.dg/torture/pr69352.c: New testcase.
Index: gcc/tree-ssa-scopedtables.c
===================================================================
--- gcc/tree-ssa-scopedtables.c (revision 232519)
+++ gcc/tree-ssa-scopedtables.c (working copy)
@@ -225,7 +225,8 @@ avail_expr_hash (class expr_hash_elt *p)
&reverse);
/* Strictly, we could try to normalize variable-sized accesses too,
but here we just deal with the common case. */
- if (size == max_size)
+ if (size != -1
+ && size == max_size)
{
enum tree_code code = MEM_REF;
hstate.add_object (code);
@@ -261,15 +262,22 @@ equal_mem_array_ref_p (tree t0, tree t1)
bool rev0;
HOST_WIDE_INT off0, sz0, max0;
tree base0 = get_ref_base_and_extent (t0, &off0, &sz0, &max0, &rev0);
+ if (sz0 == -1
+ || sz0 != max0)
+ return false;
bool rev1;
HOST_WIDE_INT off1, sz1, max1;
tree base1 = get_ref_base_and_extent (t1, &off1, &sz1, &max1, &rev1);
+ if (sz1 == -1
+ || sz1 != max1)
+ return false;
+
+ if (rev0 != rev1)
+ return false;
- /* Types were compatible, so these are sanity checks. */
+ /* Types were compatible, so this is a sanity check. */
gcc_assert (sz0 == sz1);
- gcc_assert (max0 == max1);
- gcc_assert (rev0 == rev1);
return (off0 == off1) && operand_equal_p (base0, base1, 0);
}
Index: gcc/testsuite/gcc.dg/torture/pr69352.c
===================================================================
--- gcc/testsuite/gcc.dg/torture/pr69352.c (revision 0)
+++ gcc/testsuite/gcc.dg/torture/pr69352.c (working copy)
@@ -0,0 +1,40 @@
+/* { dg-do compile } */
+
+int a[10][14], b, c, d, e, f, g, h, i;
+void bar (void);
+int
+foo (int x)
+{
+ unsigned j;
+ int k = 0, l;
+ int m;
+ if (h)
+ m = 12;
+ else
+ m = 13;
+ if (a[x][m])
+ l = (long) foo;
+ a[x][i] = l;
+ while (c)
+ {
+ if (b)
+ {
+ if (f)
+ k = 1;
+ bar ();
+ }
+ for (; d;)
+ j++;
+ }
+ while (c)
+ {
+ if (a[x][12])
+ {
+ if (g)
+ k = 1;
+ j++;
+ }
+ c = e;
+ }
+ return k;
+}
